Signature collating and binding system

ABSTRACT

Each signature feeder along a collating conveyor is selectively actuated under control of coding on optically scanned mailing labels. To compensate for the alternating thickness of different books of signatures from the collating conveyor, the coding also controls mechanical offsets for a binding line, and is compared with readings from a continuous thickness caliper. Upon detection of a malfunction at any signature feeedere, all feeders located downstream therefrom are disabled as the defective book is conveyed adjacent thereto. The defective book is rejected and a replacement book fills the empty space to prevent loss of synchronism with the mailing labels being applied by a mailing head under control of the coding.

United States Patent [191 Abram et a1.

[ SIGNATURECOLLATING AND BINDING SYSTEM [75] Inventors: Stewart J. Abram, Elmhurst; David R. Denis, Winnetka; Alex E. Heinze,

Glenview; Leonard M. Johnson, Downers; Edward Taylor, Chicago,

all of I11.

[73] Assignee: R. R. Donnelley & Sons Co.,

Chicago, Ill.

[22] Filed: Oct. 2, 1972 [21] Appl. No.: 297,993

[52] US. Cl 270/54; 270/58 [51] Int. Cl B65h 39/02 [58] Field of Search 270/52, 53, 54, 55, 56,

WHEEL TRIMMER {P DIVERTE' CIQLIPE REJEC 7" BOOKS DEMULT/PIEXER Aug. 12, 1975 4/1974 Burger et a1. 270/58 6/1974 Anderson et a1. 270/1 OTHER PUBLICATIONS Cosden, Thomas B.; SplitRun; Book Production Industry; March 1970; pgs. 34-37.

[5 7] ABSTRACT Each signature feeder along a collating conveyor is selectively actuated under control of coding on optically scanned mailing labels. To compensate for the alternating thickness of different books of signatures from the collating conveyor, the coding also controls mechanical offsets for a binding line, and is compared with readings from a continuous thickness caliper. Upon detection of a malfunction at any signature feeedere, all feeders located downstream therefrom are disabled as the defective book is conveyed adjacent thereto. The defective book is rejected and a replacement book fills the empty space to prevent loss of synchronism with the mailing labels being applied by a mailing head under control of the coding.

29 Claims, 10 Drawing Figures DOW/V SHUT-OFF DEL4Y :SH/FT courqal.

22 oo m xv 2174K PATENTEB AUG? 2 F375 SHEET 4 D 16 I TH L POSITION TRANSDUCER 1 SIGNATURE COLLATING AND BINDING SYSTEM BACKGROUND OF THE INVENTION This invention relates to a signature collating and binding system with selectively controllable signature feeders and other apparatus.

In prior insertion and binding lines, each new book of signatures such as forms an edition of a magazine has required an operator to place new signatures in signature feeders and/or to couple new signature feeders to the collating line. Various mechanical settings must be adjusted if the total thickness of the new collection of signatures changes from the prior thickness setting for the system. Generally, this set-up procedure requires adjustment of the final book caliper, the stitcher, and the mail labeler. The expense and time required to change a line has placed a limit on the number of different variations of one magazine edition which could be economically justified. However, it would be desirable to individually tailor each book of signatures according to the special interests of each subscriber.

Each variation in an edition of a magazine typically has been produced by a separate production run. lndividual subscribers which are to receive the same edition, however, are often located in different postal areas of the country Postal regulations often require that all mail for each postal area be grouped and handled as a unit. This requires large warehousing space for holding all editions, which are then sorted according to destination.

disclosed. In accordance with one embodiment, a novel book thickness caliper continuously detects the actual thickness of books of signatures for comparison with desired thickness information derived from the data which originally controlled selective actuation of the signature feeders. For better accuracy, an alternate embodiment includes a modified control which automatically produces a trial run. A caliper detects the actual thickness of each signature produced during the trial run, and stores this data in a memory. During a later production run, the stored data is combined and then compared with the output of the book thickness caliper.

Each signature feeder includes a malfunction detector. Upon detecting a malfunction, a downstream shut- Signature detectors or calipers have been provided on signature feeder boxes to detect a failure to deliver I a signature or a delivery of more than one signature.

Detection of a malfunction has activated a reject control which causes the defective book of signatures to be rejected downstream of the collating line, typically after the stitcher, and also has activated a downstream shut off to sequentially disable downstream signature feeders as the collating stations at which the malfunction had occurred is conveyed adjacent each downstream signature feeder.

Prior book thickness calipers and circuits therefore have had limited success in determining whether a detected book thickness represents a desired number of signatures. Each signature page may have a variable thickness within a given tolerance, resulting in considerable variation in the overall total thickness of abook of signatures. Furthermore, the thickness of individual signatures changes depending on moisture content, humidity of the ambient air, and other variable factors.

SUMMARY OF THE INVENTION In accordance with the present invention, the problems noted above with prior collating and binding lines have been eliminated. An information source indicates the special interest of each subscriber located within the same postal area. In response to the information source, a control individually actuates the signature feeders holding signatures which are to be provided for a particular subscriber, at the proper time that a gathering station corresponding to an individual subscriher passes the appropriate signature feeders. The time of actuation is automatically varied as spacing requirements change due to chain wear.

The overall thickness of books of signatures at adjacent gathering stations along the collating conveyor varies randomly depending on the special interests of the ofi control automatically disables all subsequent signature feeders which have been enabled by the selective control coupled to the information source.

A replacement book feeder is located downstream of the reject mechanism controlled by the book thickness caliper and a reject mechanism controlled by the signature feeders malfunction detectors. When an empty conveyor station is detected, a pre-stitched standard replacement book of signatures (not a special edition) is conveyed to fill the empty conveyor station. This prevents a loss of synchronism between the books of signatures and the information source which selectively controlled the feeding of signatures, and which operates in conjunction with a mailing label applicator.

One object of this invention is the provision of a sig nature collating system having selectively controllable signature feeders for continuously building difi'erent books of signatures on the same collating conveyor.

Another object of this invention is the provision of a signature collating system having in combination selectively controllable signature feeders which can be disabled by a downstream shut-ofi control responsive to a malfunction at any feeder.

A further object of this invention is-the provision of an improved signature collating and binding system having a replacement book feeder for supplying a replacement book of signatures to an empty conveyor station.

Yet another object of this invention is the provision of a signature collating and binding system specially adapted for processing books of signatures of continuously changing thickness, and of changing spacing with respect to a collating conveyor chain.

Still a further object of this invention is the provision of a collating and binding system having an automatically controlled trial run which provides data for controlling a subsequent production run.

Other objects and features of the invention will be apparent from the following description, and from the drawings. While illustrative embodiments of the invention are shown in the drawings and will be described in detail herein, the invention is susceptible of embodiments in many different forms and it should be understood that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention of the embodiments illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a signature collating and binding system and associated control in accordance with the present invention;

FIG. 2 is a diagrammatic illustration of a portion of one signature feeder station, along a saddle stitcher collating line, and which is shown in block form in FIG. 1;

FIG. 3 is a perspective diagram of the thin book reject station shown in block form in FIG. 1;

FIG. 4 is a cross-section of the caliper shown in block form in FIG. 1;

FIG. 5 is a diagrammatic illustration of a portion of the stitcher shown in block form in FIG. 1;

FIG. 6 is a cross-section of the replacement book feeder and the diverter, each shown in block form in FIG. 1;

FIG. 7 is a cross-section of the mailing head shown in block form in FIG. 1;

FIG. 8 is a schematic diagram of a portion of the control circuit shown in block form in FIG. 1;

FIG. 9 is a schematic diagram of another portion of the control circuit shown in block form in FIG. 1; and

FIG. 10 is a partly block and partly schematic diagram of a modified control circuit in which a trial collating run provides information for automatic control of a subsequent production run.

GENERAL OPERATION OF COLLATING AND BINDING SYSTEM In FIG. 1, a collating and binding system is illustrated for a saddle binder or sticher line. Such a system includes a large number N of signature feeders 20. For clarity, only three feeders are illustrated, labeled Box 1, Box 2, and Box N. Each feeder has a magazine 22 storing a pluraltiy of signatures 24, which are individually seized by a vacuum sucker 26 and conveyed onto a conveyor or gathering station or saddle. Each conveyor station is defined as an area preceding a pair of pins 30, illustrated in FIG. 3, which extend from a gathering or conveyor chain 32.

Returning to FIG. 1, the conveyor chain 32 is driven by a chain motor 34 in order to convey each conveyor station adjacent each of the feeders 20. It should be understood that several separate chains and associated chain motors may be provided throughout the entire system, and operated in synchronism, so as to effectively form a continuous signature conveyor means.

As each conveyor station is progressively driven past feeder station 20, a signature may be delivered thereto in order to progressively build books of signatures. After leaving the collating line of feeders 20, the conveyor station is driven past a thin book reject station 40 and a book thickness caliper 42 before reaching a stitcher 44. The stitcher includes one or more conventional stapler mechanisms for securing together the book of signatures.

The stitched or stapled book of signatures is conveyed to a diverter 48 which diverts the book onto a trimmer infeed chain 50 operated in synchronism with the signature conveyor 32. Chain 50 conveys the stitched signatures adjacent a replacement book feeder 52 and into a conventional trimmer 54. The trimmed and stitched signatures are then conveyed to a mailing head 56 which attaches preprinted mailing labels 60 by GENERAL OPERATION OF CONTROL Control information as to the signatures for a particular subscriber may be supplied by a magnetic or paper punched tape, by a central data source, or may be directly contained on the mailing label 60. By way of example, each mailing label 60 contains a code 70, see FIG. 8, which indicates the signatures to be supplied to a particular subscriber whose name and address appears on the mailing label. The labels 60 may be carried on a tape from a label source 72, FIG. 1, located a predetermined distance in advance of the vacuum wheel 62.

A sufficient number of labels 60 are exposed so that each label passes a camera 74, labeled Camera 1, when a conveyor station corresponding thereto approaches the first feeder, Box 1. Each label 60, conveyed in synchronism with movement of the conveyor chain 32 and trimmer chain 50, is applied by vacuum wheel 62 at the time that the corresponding conveyor station has reached the vacuum wheel. Thus, the mailing labels are attached to the particlar books of signatures containing the codes which controlled selective delivery of the signatures.

Camera 74 is coupled to a decoder which processes the optically scanned information and produces a series of output pulses on output lines 82 which correspond to the code being scanned. A programmable selector 84 contains a number of manually selectable switches that allows an operator to program the control so that the codes activate desired output lines 1, 2 N which control corresponding feeder Boxes 1, 2, N. Of course, the same code on labels for different magazines would not indicate that the same feeders 20 should be actuated.

Selector 84 allows an operator to preset or program the interpretation of any code. For example, selector 84 could decode a particular code and activate output lines 1, 2 and N, indicating that the label 60 then being scanned by camera 74 requires signatures from Box 1, Box 2 and Box N. For a different magazine, and a different setting of selector 84, the same code could activate output lines 1 and 3, indicating that signatures were required from Box 1 and Box 3.

Storage and delay means coupled to the output lines from selector 84 control actuation of the feeders 20 in sequence as the corresponding conveyor station is transported to a predetermined position in advance of each feeder, at which position the feeder must be actuated so that the signature feeds to the corresponding conveyor station. For this purpose, the output lines 1, 2 N are coupled to individual delay units 88, each of which may comprise a shift register shifted in synchronism with movement of the chain 32. Delay 1, which produces the shortest amount of time delay, generates an output to a Box 1 control when the first conveyor station is properly oriented with respect to feeder Box 1. Control 90 energizes (or de-energizes) a vacuum sucker control 92 so as to cause the vacuum sucker 26 to grip an individual signature 24 for delivery to the station which is or shortly will be located therebeneath.

Delay unit 2 has an additional time delay over delay unit 1 which is equal to the time necessary for the conveyor station to travel from Box 1 to Box 2. The Box 2 control 90 has an output as the conveyor station corresponding to the previously read label 60 reaches feeder Box 2. It should be noted that the previously read label 60 will have been stepped by source 72 a corresponding distance (closer to mailing head 56) in synchronism with the movement of the conveyor chain 32.

Each subsequent delay 88 produces an additional time delay corresponding to the distance between feeders 20. If selector 84 had not produced an output on any particular output line, the corresponding delay unit 88 would not have received an energizing signal, and its corresponding box control 90 would not have been enabled when the conveyor station was adjacent thereto. Thus, the control selectively actuates the feeders 20 so as to progressively build on the conveyor stations books which may contain different signatures, as controlled by the information contained on the mailing labels 60.

Book thickness caliper 42 located downstream from the last feeder Box N determines whether the total thickness of a book of signatures corresponds to the number of signatures which should have been selected under control of the code carried by the label corresponding to that book. This requires that the coded control information be retained and delayed until the corresponding book reaches caliper 42. The necessity for additional shift registers or other delay means is eliminated by locating a second camera 100, labeled Camera 2, at a position to scan each label 60 which had been read by camera 74 at the time that the book corresponding thereto reaches caliper 42.

The code read by camera 100 is translated into a thickness signal representing the number of signatures which should have been selected. This calculated signal is coupled to a comparator 102 for comparison with an actual thickness signal from a sensor 104 in caliper 42. Thus, the second camera serves to preclude the need for additional shift registers and serves as a proofreader for the first camera, insuring that the system will not apply labels out of sequence to several books of signatures, should the labels become out-of-phase with the books due to some system malfunction.

Camera 2 requires use of some of the same decoding circuits as used for Camera 1. While duplicate circuits could be provided, a time sharing circuit allows circuits to be used in common. A multiplexer 110 and a demultiplexer 112, located between decoder 80 and selector 84, effectively switches optical decoding circuits between cameras 74 and 100. When camera 74 is to be effective, multiplexer 110 connects the video output of camera 74 to decoder 80, and demultiplexer 112 connects the output lines from selector 84 to the inputs of delay units 88. Conversely, when camera 100 is to be effective, multiplexer 1 connects the video output of camera 100 to decoder 80, and demultiplexer 112 connects the output lines from selector 84 to a summer 1 16 associated with the caliper channel. The time necessary to scan a label by either camera is a small fraction of the time each label is within the scanning field of the cameras.

When camera is effective, summer 116 adds together the number of signatures (with appropriate scale factors, if desired) which should have been delivered to the conveyor station then adjacent the caliper 42, as represented by actuated ones of the lines 1, 2 N. The resulting digital representation of the total thickness of signatures is coupled to a digital-to-analog (D/A) converter 120 which produces on output line 121 an analog signal having a magnitude corresponding to the digital input to the converter 120. Line 121 is coupled directly to an analog input 124 of the comparator 102.

The output of sensor 104 is an analog signal having a magnitude corresponding to the thickness of a book then contacting a sensing probe 126. A cycle control switch produces an output signal when the probe 126 is contacting a portion of the book which will provide valid thickness information. Switch 130 enables an analog gate 132 which passes the analog signal from sensor 104 directly to a second analog input 134 of comparator 102.

Comparator 102 is a conventional analog voltage comparator which determines whether the analog signals at inputs 124 and 134 are substantially equal. If the signals are equal, comparator 102 does not produce any output. However, if the analog signals are unequal by at least a predetermined range, comparator 102 produces an error pulse output which is coupled to a shift register delay unit 136. Delay 136 produces a time delay C which corresponds to the time necessary for the book then being read by caliper 42 to travel past stitcher 44 and to the diverter 48. An error output from comparator 102 thus synchronously follows the book and actuates a book selector 140 to cause the book to be diverted to a reject station 142. Book selector 140 normally diverts books onto the trimmer chain 50, and thus no output from comparator 102 allows the book to pass without being rejected.

Books which have not been rejected are conveyed by trimmer chains 50 past replacement book feeder 52 to the trimmer 54, and then to the mailing head 56. The mailing head includes a height control which adjusts the relative height of the vacuum wheel 62 relative to a label base carrier. The height adjustment 150 is controlled by a digital thickness signal from summer 116, after passing through a shift register time delay unit 152 which produces a time delay E corresponding to the time necessary for a book to be transported from caliper 42 to the mailing head 56.

Certain of the mechanical settings for the binding line must be adjusted or compensated for the continually varying thickness of the books being delivered thereto. Some machines such as trimmer 54 may be constructed to accept a variety of thicknesses without requiring adjustment. However, other machines such as stitcher 44 require a thickness setting of other mechanical offset for each book being delivered thereto. A thickness adjustment control 156 on stitcher 44 is responsive to a digital thickness signal from a shift register delay unit 158 coupled to summer 116. Digital delay unit 158 produces a time delay D which is equal to the time required for a book to travel from caliper 42 to stitcher 44.

Each feeder 20 includes a detector switch 160 which has an output when a malfunction occurs at that feeder. For a saddle binder line, switch 160 may comprise a missing signature switch which produces an error signal when the feeder has failed to deliver a signature. For

other types of collating and binding lines, switch 160 may take other forms, such as a double signature detector actuated when two signatures are fed in response to one feeder actuation.

Each detector switch 160 is coupled to a set input of a corresponding flip-flop stage in a downstream shutoff shift register 162. The shift register 162 has a number of stages equal to or greater than the number of feeders 20, to cause a pulse stored in the shift register 162 to be shifted therethrough in synchronism with the movement of the conveyor chain 32. Each register stage just prior to a feeder (except for the first feeder) has a disable output line 164 which is coupled to the box control 90 for that adjacent feeder.

By way of example, it will be assumed that switch 160 in Box 1 has detected a malfunction. The resulting error signal is stored in shift register 162 and is shifted in synchronism with movement of the conveyor chain 32 and hence with movement of the conveyor station at which a malfunction had occurred. Just prior to the conveyor station reaching Box 2, the disable line 164 connected to Box 2 control 90 has an output which disables the control, preventing an enable output (if any) from delay 2 from actuating sucker control 92. Meanwhile, the error signal continues to be shifted through the shift register 162, disabling each box control 90 as the conveyor station with the defective book of signature(s) reaches the feeder 20 corresponding thereto. The final output from the collating line is a thin book which is missing a number of signatures proportional to the position at which a malfunction first occurred.

The thin book could be allowed to pass through caliper 42 and stitcher 44 for rejection by the diverter 48. However, the possible substantial lack of thickness of the book could cause the stitcher 44 to malfunction. Therefore, thin book reject station 40 is located prior to the location of the stitcher 44. The reject station 40 includes a diverter solenoid 170 which, when actuated, diverts a thin book of signatures from conveyor chain 32 to a reject book station 172. To actuate solenoid 170, a shift register delay unit 174 is interposed between the last stage of shift register 162 and the solenoid 170. Delay unit 174 has a time delay A which corresponds to the time necessary for a book to travel from the last feeder box N to the thin book reject station 40. Thus, the error signal which causes a downstream shut-off of the feeders ultimately actuates solenoid 170 in order to reject the thin book.

If a particular stitcher 44 has a sufficient tolerance to thickness variations, or if only a small number of feed ers 20 are being utilized, then thin book reject station 40 may be eliminated and delay unit 176 may be interposed between the output of delay unit 174 and the input of delay unit 136. Delay unit 176 may be a shift register having a time delay B corresponding to the time necessary for a book to travel from a position corresponding to station 40 to caliper 42. Thus, the error signal would be shifted by a time delay A-l-B+C and cause actuation of book selector 140 when the thin book reached the diverter 48. If desired, delay unit 176 may be used in addition to reject station 40, as a safety precaution to insure that a thin book does not reach the mailing head 56 due to a malfunction of the thin book reject station 40 and/or the caliper 42.

To shift all of the delay units and the shift registers, a shift control 180 driven by motor 34 generates shift pulses for recurring equal increments of movement of the conveyor chain 32.

Replacement book feeder 52 causes a replacement book of signatures to be fed to the trimmer chain in order to replace books which have been rejected by stations 40 and 48. A switch 184 is located to detect an empty conveyor station at a time when a book should be present. Upon detection of an empty conveyor station, the switch 184 actuates a valve solenoid 186 to cause a replacement book to be conveyed to the empty conveyor station. Thus, the label corresponding to a previously rejected book will be applied to the replacement book, insuring that subsequent labels do not lose synchronism with their associated books of signatures.

Should the replacement book feeder 52 fail to operate, a loss of synchronism between the labels 60 and the books of signatures would result. To prevent this occurrence, a switch 188 is located to detect an empty conveyor station just prior to the mailing head 56. Should an empty station be detected by switch 188 when a book of signatures should be present, a master stop control 190 is actuated and disables chain motor 34 to stop both the conveyor chain 32 and the trimmer chain 50. After an operator has rectified the error and has placed a replacement book at the detected empty position, the stop control 190 is deactuated in order to allow continued operation of the system. Certain of the novel machine components and controls shown in block form in FIG. 1 will now be described with reference to the remaining drawings.

SELECTIVELY- ACT UABLE FEEDER In FIG. 2, a feeder station 20 is partially illustrated. Each feeder 20 has a primary drum or cylinder 200, a transfer drum or wheel 202, and an opener drum or wheel 204, driven in synchronism by means of a main drive mechanism 206 coupled through a clutch (not illustrated) to a common drive shaft. The clutch allows the main drive mechanism 206 to be coupled to the main drive shaft at any desired point in the delivery cycle. This allows the feeders to be located at distances different than the original spacing between each saddle, i.e., the original distance between pins 30 in FIG. 3.

Vacuum sucker 26 is coupled to a conventional slide valve which in turn is coupled to an output line 210 of a valve 212 which alternately connects line 210 between a vacuum line 214 and an exhaust line 216. Valve control 92 controls the state of valve 212. During each cycle of operation of the feeder, vacuum sucker 26 is extended and the vacuum is applied in order to pull an individual signature away from the magazine and against the cylinder 200, where it is retained by a primary drum gripper 220 and is pulled around the upper cylinder 200 as the cylinder is rotated by the main drive mechanism 206.

At the farthest extent of its travel, the primary drum gripper 220 releases the signature into a register stop. Tucker blades position the lower portion of the signature into the transfer drum and grippers 224. The opener drun 204 then rotates so that the short fold of the signature corries in contact with an open gripper 226 on wheel 202. The open gripper 226 separates the short fold from the long fold as the signature approaches the saddle chain 32. Both folds are then released from grippers 224 and 226 and the signature is forced down over the gathering chain saddle in a known manner. Missing signature detector switch 160 is located at any suitable position so as to detect whether the primary drum 200 has received a signature.

If desired, the vacuum control 92 may be replaced by a mechanical solenoid control 92, shown in dashed lines, which mechanically latches the vacuum sucker 26 to prevent its engagement with a signature. For this purpose, the vacuum valve 92 is replaced by the mechanical solenoid which operates a linkage 230 in order to rotate a latch or catch 232 into engagement with the conventional mechanism which extends the vacuum sucker 26 when a new signature is to be gripped.

The system control must actuate either of the controls 92 or 92' at the proper point in the feeder cycle of operation. Otherwise, an individual signature will be delivered too soon or too late with respect to the saddle pins 30 (see FIG. 3). To detect the proper time for actuation of control 92 or 92, a proximity switch 236 has a probe 238 which rides on a timing cam 240 rotated in synchronism with the primary drum gripper 200 and hence in synchronism with the main drive mechanism 206. The actuating portion of cam 240 is located so that the proximity switch 236 is actuated immediately prior to the proper time for actuation of control 92 or 92'. The output of the proximity switch 236 is coupled to the box control 90, as will be explained later. For clarity, this timing connection has not been illustrated in FIG. 1. The remaining operation of the feeder is conventional and will not be described further.

THIN BOOK REJECT In FIG. 3, the thin book reject station 40 is illustrated in detail. A pair of lifter arms 250 is illustrated in broken lines in a lowered or bypass position and in solid lines in a raised or reject position. Arms 250 are pivotally mounted on a base plate 254 which supports the lift solenoid 170. When the solenoid 170 is actuated (as illustrated), a solenoid arm 256 is pulled into the solenoid 170, pivoting a lever 258 and connected link 260 so as to rotate a pivoted plate 262 downwardly within a central opening in plate 254. The connection to plate 262 and the pivot connection of the arms 250 to plate 254 causes the lifter arms 250 to rise from the bypass position and converge adjacent a reject book guide 270. The pressure of the pins 30 against the book of signatures 24 causes the book of signatures to ride up the lifter arms 250 and via the book guide 270 to pairs of oppositely rotating pinch rollers 274 and 276 which pull the book off of the gathering chain 32 and into a second book guide 280 with pinch rollers connected so as to deposit the rejected pin books in the reject tray 272.

When lift solenoid 170 is not actuated, the lifter arms 250 remain in the bypass position in which the gathering chain 32 and pins 30 convey a book of signatures past the reject station 40 and to the remaining stations of the binding line.

BOOK THICKNESS CALIPER In FIG. 4, the caliper 42 is illustrated in detail. Sensor 140 may comprise a linear variable-differential transformer (LVDT) which has an output voltage proportional to the linear distance a probe mechanism 126 is offset or extending with respect to the stator portion of the LVDT. The fixed or stator portion is mounted to a bracket 300 which is fixed with respect to the gathering chain 32. The LVDT probe mechanism 126 is formed as, or can be attached to, a yoke shaped member which rotatably mounts a roller 302 which engages a disc 304 mounted on a linearly movable, spring loaded shaft 306. The disc 304 extends through an opening in a guard plate 308 which supports the book of signatures 24 as it is conveyed past the caliper station 42.

To support the book of signatures opposite the movable probe assembly, a quadrant cam 310 is rotatably mounted to a timing shaft 312 which is rotated in synchronism with movement of the conveyor chain 32. Timing switch 130 is located so as to be actuated only when the extending quadrant of the cam 310 is engaging the book of signatures. When a book of signatures is properly located with respect to the disc 304, the quadrant of the cam 310 presses against the other side of the signatures in order to form a fixed reference position.

The probe 126 is urged by a spring 314 outwardly with respect to the stator of the LVDT 140. This causes the roller 132 to linearly move the disc 304 against the signatures which are being supported by the quadrant cam 310. The gap between the disc 304 and the cam 310 corresponds to the thickness of the signatures, and hence the output of the LVDT while switch 130 is actuated represents the total book thickness. If desired, a dash pot 316 may be attached to the rotor shaft of the LVDT 140. Movable shaft 306 may be constrained against movement beyond a position which represents a zero caliper gap with respect to the cam 310. The shaft 312 rotates the earn 310 beyond a position which actuates switch 130 before the book of signatures is transported by the gathering chain 32 beyond the caliper station 42.

STITCHER THICKNESS COMPENSATION In FIG. 5, the thickness adjustment or compensation mechanism for the stitcher 44 is illustrated in detail. One or more conventional stitcher heads 330 are driven reciprocally by a stitcher drive 332 which rotates a driver cam 334 and a bender cam 336. A follower driver linkage 340 transfers motion of the driver cam 334 to a driver bar 342. Similarly, a follower bender linkage 344 transmits the eccentric motion of the bender cam 336 to a bender bar 346. The driver bar 342 and bender bar 346 are connected to any desired number of stitcher heads 330 in order to simulatneously drive all stitcher heads downwardly against an adjacent book of signatures 42, as it is held against the gathering chain 32 by a holddown roll 350 and a slide gripper 352.

A position adjustable link 354 interconnects the pair of follower linkages 340 and 344 and controls the thickness adjustment for the stitcher. The link 354 is moved upwardly to provide an adjustment for thinner books, and is moved downwardly to set the stitcher for thicker books. Vertical adjustment of the link 354 is controlled by an eccentric 360 which includes a link 362 and associated over travel spring 364 attached to a fork 366 which slidably engages a pin 368 of an eccentric cam 370 which has a one-toone relationship with-the stitcher. As is well known, rotation of the eccentric cam 370 will vertically adjust the height of eccentric 360 which bears against adjustable link 354, thereby adjusting the stitcher for different thickness books.

In accordance with the present invention, a digital position transducer 156 has an axially positionable shaft 374 which moves vertically in proportion to a digital signal which is coupled to the transducer 156. A cam stop 376 is attached to the end of the shaft 374 and forms a stop or restraining surface for the link 362. The arcuate shape of the restraining surface produces an adjustable stop for different vertical positions of the shaft 374. Alternatively, the transducer could control a small hydraulic servo system which would move the stop, thus increasing the available amount of torque. Since the stitcher thickness adjustment need not be highly accurate, the stepped cam stop mechanism can be responsive to only the most significant bit outputs of the summer 116.

REPLACEMENT BOOK FEEDER In FIG. 6, diverter station 48 and replacement book feeder 52 are shown in detail. The diverter station 48 is conventional and includes a drive roller 400 which conveys books to the trimmer infeed conveyor chain 50, and a drive roller 402 which serves to convey books to the reject tray 142. A tucker blade mechanism 404 along with pickup rollers 401 urge the book upwardly to one of the drive rollers.

Trimmer infeed chain 50 includes a plurality of lugs 410 which carry the books past the replacement book feeder 52 and towards the trimmer. A book hopper 412 carries in an upper or buffer section a plurality of replacement books 414 for filling an empty conveyor space. A pair of minimum pile height detectors 418 and 419 maintain a minimum height of replacement books within a lower or active store section of the book hopper 412. When the books in the lower section fall below the height of detectors 418 and 419, a pile height controller 420 is actuated to release a predetermined height of replacement books, which fall to replenish the diminishing supply of replacement books held in the active section.

The lower section of the book hopper 412 includes a book pile support 422 which is lowered when a book is to be fed to a replacement book flight chain 424. The position of the support 422 is controlled by an air cylinder 426 which is pneumatically controlled by a valve solenoid 1 86. The valve solenoid also includes a section for pneumatically controlling a vacuum slide 430 which grips and releases the lowermost replacement book during a replacement cycle. The vacuum slide is reciprocally driven by a link 434 operated under control of a shuttle cam 436.

Detector switch 184 has an extending arm 440 which is lowered when no book is located in front of a lug 410. This transmits a signal to a control 442 which actuates solenoid valve 186 when the signal is present at a time when the arm 440 should be contacting a book. A timing signal which indicates that a book should be present may be a switch positioned to be tripped by lugs 410, or a timing cam and switch operated in synchronism with movement of chain 50.

When valve 186 is actuated, air cylinder 126 lowers support 422 while the vacuum slide 430 grips the lowermost replacement book. The shuttle cam 436 is then rotated, causing link 434 and connected vacuum slide 430 to be moved to the right as illustrated in FIG. 6. This moves the lowermost replacement book into engagement with speeder rollers 450. As the replacement book enters the speeder rollers 450, the valve solenoid 186 releases the vacuum on the vacuum slide 430. The replacement book is conveyed onto a slide 454 and is urged by lugs 456 on chain 424 downwardly until it falls onto the empty conveyor station. Meanwhile, the shuttle cam 436 moves the vacuum slide 430 back to the illustrated position, and solenoid valve 186 actuates air cylinder 426 in order to move the support 422 upwardly in preparation for the next replacement cycle.

MAI LING HEAD ADJUSTMENT In FIG. 7, the mailing head height adjustment mechanism is illustrated in detail. The mailing label vacuum wheel 62 is fixed in height and operates in a conventional manner to attach individual labels 60 to the book of signatures being transported thereby. Conventional means (not illustrated) feeds the tape of mailing labels to the vacuum wheel 62 and conveys the books of signatures past the vacuum wheel.

A book carrier, such as a brass shoe 470, is vertically adjustable in height under control of a hydraulic cylinder 150 which is controlled by the digital signal from delay unit 152 (see FIG. 1), which signal in turn may comprise only the two most significant bits from summer 116 to provide a thick, medium, thin, or zero adjust. Each digital increase causes a shaft 472 to extend further outwardly against a link 474. The link 474 is pivotally mounted to a base 476, and has an opposed end which is pivotally mounted to the shoe 470. A leveling link 480, similar to link 474, is pivotally mounted to base 476 and to shoe 470 in order to maintain the shoe 470 in a horizontal plane. The leading edge 482 of the shoe 470 is inclined to allow passage of the book of signatures from a lower guide plate 484 onto the top of shoe 470.

In operation, the thickness adjustment mechanism for the mailing head raises or lowers each individual book of signatures with respect to the fixed vacuum wheel 62. The vacuum wheel has been fixed in height since the inertia of the shoe 470 is considerably less than the inertia of the vacuum wheel 62 and associated feed mechanism. However, it will be appreciated that the vacuum wheel could be made adjustable with respect to a fixed height lower support for the books of signatures.

CODE DECODER AND SELECTOR CIRCUITS In FIG. 8, a portion of the optical scanning and decoding circuits shown in block form in FIG. 1 have been illustrated in detail. Code on each mailing label 60 consists of a track or space mark 500 followed by binary coded demographic data, such as can be repre sented by four letter fonts or characters which represent eight binary bits. Each vertically extending line in the letter characters represent a I bit, whereas no vertically extending line at the corresponding bit location represents a 0 bit. The code 70 is read by cameras 74 and during horizontal scan periods which cover or scan the intermediate portion of the characters, so that the top and bottom portions of the characters have no code significance. This allows a single conventional font, either typed or printed, to represent two binary bits. In the present example, the character L represents the binary bits 10; the character J represents the bits 01; the character 0 represents the bits 11; and no letter (a blank space) represents the bits 00. Thus, eight binary bits are represented by only four letters. Space mark 500 has a black area of a width greater than any letter or number character on the entire mailing label 60.-

Cameras 74 and 100 may comprise conventional remote control TV cameras focused so that their field of view is limited to that portion of the label that contains the coding 70. Since the labels are neither accurately stopped nor accurately printed with respect to each other, the scanning operation is not limited to only a single pass, but rather the entire intermediate height area in which the code 70 may be located is scanned a plurality of times.

Decoder 80 is coupled by multiplexer 110 to either camera 74 or camera 100. Assuming by way of example that camera 74 is coupled by multiplexer l to decoder 80, the video output signal therefrom is coupled to an AND gate 510. The other input to AND gate 510 is a new label signal generator 512, which is interconnected with the label source 72 (FIG. 1) in order to generate a new label signal when the labels are sequenced or stepped so that a new label appears in the scanning field. The video signals are gated to a black level detector 514 which has an output on a line 515 whenever the video signals fall into a black level range.

The black level signals on line 515 are coupled to a mark width detector 518 which produces an output signal on a line 519 only when the black level signal on line 515 exists for a predetermined length of time which corresponds to the width of the space mark 500. When this occurs, line 519 has an output which occurs simultaneously with the trailing edge of the space mark. This output is coupled to a logic gate 522 and to a counter 524.

To increase reliability, the space mark must be detected for a predetermined number of TV scan lines. Counter 524 counts each trailing edge of the space mark, as indicated by the signal on line 519, until a predetermined count is reached which corresponds to an intermediate height position of the space mark 500 and associated coding characters 70. The predetermined count causes counter 524 to produce an enabling output which is coupled to logic gate 522.

Upon detection of the next trailing edge of the space mark, logic gate 522 has both of its inputs enabled. This produces an enabling output to an AND gate 530 and an AND gate 532. The enabling output lasts for a predetermined length of time corresponding to the time necessary to complete one horizontal scan of the four code characters. After the lapse of this time period, logic gate 522 disables the AND gates 530 and 532. The AND gate 530 allows an output pulse to be coupled to a binary-to-decimal circuit 536 for each occurrence of a black signal while logic gate 522 has an enabling output. Each black signal in turn represents a vertical line of one of the code letters.

A high frequency clock 538 produces a clock pulse each time the TV camera has scanned to a position at which a vertical line should appear if a 1 bit is present. The first clock pulse passed by AND gate 532 steps a binary counter 540 to an output representing 0001. The binary-to-decimal circuit 536 is responsive to the 0001 count to couple the output of the AND gate 530 to the first output line. If a 1 bit is now present, the black signal will be passed through circuit 536 and recorded in a summer 544. If a 0 bit was present, the summer 544 would not record a signal.

As the TV scan signal reaches the next bit position, clock 538 has a second clock pulse which causes binary counter 540 to step to output 0010. This causes circuit 536 to connect the output from AND gate 530 to the second summer 544 (second from the right as illustrated in FIG. 8). The above described operation continues until clock 538 has counted through the last binary bit position. Shortly thereafter, the enabling output from gate 522 is terminated and the AND gates 530 and 532 are blocked.

During the next horizontal scan period, the space mark 500 will again be detected by detector 518, producing an output on line 519 which again enables logic gate 522 (since counter 524 still has an enabling output). Gate 522 in turn enables AND gates 530 and 532, allowing a new counting cycle to be initiated. Binaryto-decimal circuit 536 again passes pulses occurring at the time slot or location of the bit positions to corresponding ones of the summers 544.

The summers 544 produce output signals only when a predetermined count or sum is reached, which may be varied depending on the quality of the characters which form the code 70. The summers 544 thus allow for discontinuities in printing, while insuring that a spurious spot on the label 60 will not produce a falso bit output. After a preselected number of intermediate lines have been scanned, a circuit (not illustrated) clears counter 524, thus resetting the decoder for the next decoding operation. Output lines 82 of summers 544 thus have signals representing 1 or 0 bits, depending on whether the predetermined count was reached in the corresponding summers.

Similar binary codes will represent different signatures to be delivered depending on the particular edition of a magazine being produced. Selector 84 contains a plurality of manually actuable switches which allow an operator to program the selector so that any 1 or 0 bit, on any of the output lines 82, will enable a desired Box 1, 2 N. A plurality of Box 1 switches 550 allow any one of the output lines 82 to be interconnected with a line 551 which controls Box 1. A plurality of switches 554 allows any of the output lines 82 to be interconnected with a line 555 representing Box 2. The above described pattern continues through a plurality of switches 558 which allow any of the output lines 82 to be interconnected to the last output lines 559 corresponding to Box N.

The output lines from the selector 84 are coupled to the demultiplexer 112 which switches the lines to delay units 88, if camera 74 is coupled by multiplexer l 10 to decoder 80, or to the summer 116 if multiplexer 110 is coupling camera to decoder 80. A multiplex control 565 produces a signal when multiplexer and demultiplexer 112 should couple the decoder 80 between camera 74 and the delay units 88. An oppositely going signal from multiplex control 565 causes decoder 80 to be switched between camera 100 and the summers 116. Demultiplexer 112 may take any conventional form, such as a plurality of switches 567 which interconnect the Box input line to either of two outputs depending on a switching signal on a line 568 from the multiplex control 565.

FEEDER DELAY AND CONTROL CIRCUITS In Flg. 9, the delay 88 and box control 90 for each of the feeders is shown in detail. By way of example, the illustrrated feeded is identified as Box N, but it will be understood that the circuit is the same for each feeder. Delay unit 88 comprises a shift register having a numher of stages corresponding to the number of incremental distances between a reference position just preceding Box 1 to the Box N position. Each binary O to 1 bit from the selector output line N is entered in the illustrated shift register 88 and is shifted downwardly for each shift pulse from the shift control 180 (FIG. 1). When the corresponding gathering station reaches Box N, a shift pulse shifts to an output line connected with Box control 90 the bit for that gathering station.

Control 90 provides an automatic fractional adjustment of the length of a shift register which corresponds to one stage of the shift register 88. This provides an automatic timing adjustment to compensate for growth of the collating chain 32. As is well known, wear' between the connecting pins of a collating chain causes the inter-book distance to grow or lengthen over the useful life of the chain. Although the number of collating stations remains constant, the distance between stations increases sufficiently to require compensation.

Typically, this is accomplished by an operator disabling the feeder clutch (see prior discussion on Selectively Actuable Feeder), and moving the feeder station with respect to the master drive shaft. Then, the clutch is engaged in order that the master drive shaft will drive the cycle chain 260 (see FIG. 2) at a proper time in the delivery cycle so that a signature is properly fed onto the saddle. Thus, the distance between adjacent feeders is manually changed over the useful life of a collating chain.

Box control 90 allows the overall length of the fractional stages to be lengthened or shortened so that feed solenoid 92 is actuated at the proper time when the proximity switch 236 indicates that a signature is to be fed onto an adjacent saddle. Any change in feeder position, which in turn produces a slight change in the timing cycle as indicated by an increase or decrease in time when switch 236 is actuated, is automatically compensated for by the illustrated circuit.

An eight-stage shift register 600 has a separate output line 601 from each of the eight stages. The output lines 601 are coupled to inputs of a multiplexer 604 which has a single output line 605. The multiplexer 604, in response to a binary count on input lines 1, 2 and 4 from a binary counter 608, couples a corresponding one of the lines 601 to the line 605. For example, if binary counter 608 maintains a binary output 100 on lines 4, 2 and 1, respectively, multiplexer 604 causes the fourth input line 601 to be directly coupled to output line 605. Thus, all pulses on the fourth line 601 will be directly passed to line 605. j

The multiplexer output line 605 forms a data input to a five-stage shift register 610 having individual stages 611, 612, 613, 614 and 615. A shift input of shift register 610 is coupled to a clock 620 which operates at five times the rate of the shift control 180 of FIG. 1. The output of clock 620 is also coupled to the shift input of shift register 600. Thus for each single shift operation of shift register 88, clock 620 causes shift registers 600 and 610 to shift five times.

If binary counter 608 receives a pulse on an UP input line, as the result of an operator change, the binary output count is increased by one binary number. This causes multiplexer 604 to connect the next decimal higher line 601 to output line 605. Since the next higher output line 601 is connected to the next stage of the shift register 600, the output pulses on line 605 occur one clock cycle (of clock 6 20) later, that is, 1/5 cycle later with respect to the shift pulses to shift register 88. This results in the feed solenoid 92 being actuated at a later increment of time, corresponding to l /5 cycle. Conversely, if binary counter 208 had received a pulse on a DOWN input line, the output count would have been decreased by one, causing multiplexer 604 to connect an earlier stage of shift register 600 to output line 605. This results in feed solenoid 92 being actuated at an earlier increment of time in the delivery cycle.

An UP logic circuit 630 determines from shift register 610 and proximity switch 236 when the binary counter 608 must be stepped up by one count. Conversely, a DOWN logic circuit 632 determines from the shift register 610 and proximity switch 236 when the binary counter 608 must be stepped down a count in order to react to an operator change. These logic circuits are effective when a 1 control bit is present, that is, when a feeder solenoid is to be actuated. Of course, when a 0 control bit is present, the solenoid 92 is not actuated. A 0 control bit can cause a change if preceded or followed by a 1. If the circuit were to receive only ls or only Os it would not work. It takes either followed or preceded by the other, and therefore may take several cycles to compensate for an operator adjustment.

Logic circuit 630 is onnected to the output lines of stages 611 and 612, and produces an output pulse on the UP line when stages 611 and 612 register a 01 or l0, respectively, at the time when proximity switch 236 produces a gating pulse. If stages 611 and 612 have either a 00 or a l 1 output at this time, circuit 630 does not produce any output pulse. Logic circuit 632 is similar to circuits 630, but is connected to the output lines of stage 614 and 615. If these stages have either a 01 or 10 output when switch 236 generates a gating pulse, then a pulse is produced on the DOWN output line. However, if stages 614 and 615 have either a 00 or 1 1 output when the pulse from switch 236 occurs, then no pulse is generated.

When control 90 is properly timed, shift register 610 receives the same control bit in all five stages 61 1-615 at the time that switch 236 has an output. As a result, neither the UP logic circuit 630 nor the DOWN logic circuit 632 produce an output which would change the count then being maintained by the binary counter 608. The center stage 613 is coupled to an AND gate 636 which also receives an input from the proximity switch 236. When the proximity switch provides a gating output, the control bit then stored in stage 613 is gated through AND gate 636. If a 1 bit is stored, feed solenoid 92 is actuated and causes a signature to be fed onto the adjacent saddle. If a 0 bit is stored, then AND gate 636 would not pass a pulse to feed solenoid 92.

Due to chain wear, it will be assumed that an operator has disengaged a feeder clutch and has moved the illustrated feeder station N further downstream. It should be noted that the count previously held in binary counter 608 will not be proper for the new position of the feeder station. When the feeder clutch is now engaged, pulses will be coupled through multiplexer 604 to shift register 610, as previously described. However, when the first entered control bit reaches the last stage 615, proximity switch 236 will not produce an output pulse because the feeder is operating at a later point in time.

The next clock pulse from clock 620 causes the first entered control bit (herein assumed to be a 1 bit) to be shifted out of the last stage 615, i.e., the pulse is cleared. The last entered 1 control bit is not shifted to stage 612. As a result, the stage 611 records a bit while stage 612 records a I bit when proximity switch 236 has an output pulse. This causes circuit 630 to produce a pulse and step up binary counter 608 by one unit in order to compensate for the new position of the feeder station. The middle stage 613 still allows the feed solenoid 92 to be actuated at the proper time.

Downstream shut-off shift register 162 comprises a number of separate stages, such as flip-flop FF, which shift pulses to the right as illustrated in FIG. 9. Each Box control 90 corresponds to a particular FF stage in register 162. When AND gate 640 receives an enabling pulse from both AND gate 636 and from the output of the missing signature switch 160, and error pulse is recorded in an FF stage 642 which corresponds to the position of control 90. Assuming that control 90 represents other than the last feeder, then the error pulse is shifted to the right in order to disable downstream feed solenoids 92 when the collating station at which the error had occurred reaches each of those feeder positions.

At each feeder, a FF stage 644 preceding state 642 has an output which disables AND gate 636 when an error pulse is shifted to that stage. This blocks enabling of feed solenoid 92 even though a I control bit is present in stage 613 when switch 236 has an output. The stage 644 may be a stage immediately prior to stage 642, or may be prior by a plurality of stages, depending on timing requirements which in turn depends on the distance represented by each stage in shift register 162.

The control system of FIG. 1 may be modified as illustrated in FIG. in order to automatically control a trail run, monitor the actual thickness of books produced during the trial run, and then control a production run by using data developed during the trial run. Only so much of the control as has been changed, or which is necessary for an understanding of the invention, has been illustrated in FIG. 10. It should be noted that a separate decoder 80 and selector 84 have been provided for each of the cameras 74 and 101), eliminating the multiplexer and demultiplexer previously used. The portions of the circuit not illustrated may take the form previously described.

After the collating and binding line has been adjusted to produce new books of signatures, the selectors 84 are set identically. The chain motor is energized, and then a set up switch 650 is actuated in order to automatically produce a trial run of signatures. An AND gate 654, in response to actuation of the set-up switch 650 and the occurrence of a shift pulse from the shift control 180, passes a pulse to a number generator 656 which may comprise a ring counter for sequentially actuating each output line. In turn, each output line is coupled to a different one of the delay units 88, in order to actuate the associated Box control 90 when the collating station reaches the associated feeder. For example, the first output pulse from AND gate 654 will cause number generator 656 to actuate delay 1. Upon the occurrence of the second shift pulse from shift control 180, the second pulse from AND gate 654 will cause number generator 656 to actuate its second output line, thereby actuating delay 2 (not illustrated). Each feeder box is likewise sequentially actuated so that the output of the collating line is a series of individual signatures each from a different feeder.

During the trail run, decoder and selector 84 associated with camera 1 are inoperative. The set-up switch 650 produces a signal which is negated by a NOT gate 664 in order to disable an AND gate 662 which is inserted between camera 1 and the decoder 80.

At the same time that number generator 656 is enabled by a shift pulse from AND gate 654, the shift pulse is also coupled to a delay shift register 670 having a time delay equal to the time required for a collating station to travel past the entire collating line, the thin book reject station, and reach caliper 42. At the time when the station has reached caliper 42, delay 670 produces a pulse to a write counter 672, which may be similar to number generator 656. The write counter 672 individually actuates the write gate of a memory 680 corresponding to the feeder box which had delivered the signal then passing the caliper 42.

For example, the first pulse passed by AND gate 654 causes number generator 656 to actuate delay 1 and the Box 1 control. At the time that the collating station carrying this signature reaches caliper 42, delay 670 produces an output pulse coupled to write counter 672. This actuates write gate line 1 and hence memory Box 1. The thickness of the signature, now being read by caliper 42, produces an analog signal which is converted by an analog-to-digital (A/D) converter 684 into a corresponding digital signal which is now gated or written into memory Box 1.

Similarly, as the signature from the second feeder reaches caliper 42, delay 670 produces an output pulse which steps write counter 672 to output line 2, actuating memory box 2 and causing the thickness signal to be stored therein. As each further signature is selectively actuated, its thickness is ultimately recorded in corresponding ones of the storage memories 680.

After number generator 656 steps to its last output, it is disabled until the set-up switch 650 is again actuated, for the next trial run. The last output of write counter 672 may be used to deactuate the set-up switch 650, or to otherwise indicate that a production run may begin.

To begin a production run, a run switch 700 is actuated, thereby actuating read gates 702 which individually coupled each output line from the selector 84 of camera 2 to a corresponding read gate input of the memory 680. At the same time, AND gate 662 couples camera 1 to its associated decoder 80. As each mailing label passes camera 1, the code thereon is decoded and causes selector 84 to actuate the appropriate delay units 88. For example, this may cause delay 1 and delay N to be actuated in response to a particular code on a mailing label. This mailing label reaches camera 2 at the time that the collating station carrying the signatures from Box 1 and Box N reaches caliper 42.

The mailing label is read by camera 2 and causes selector 84 to actuate the output lines associated with Box 1 and Box N. The output lines pass signals through gates 702 to the read out gate inputs of memory box 1 and memory box N, causing the thickness signals stored therein to be read out and passed to a summer 710. The summer 710 adds together all of the digital inputs thereto, producing a sum total which is converted by a digital-to-analog (D/A) converter 712 into a corresponding analog signal coupled to a comparator 714.

At this time, comparator 714 is receiving an analog input from the caliper 42 which is monitoring the collating station carrying the signatures from Box 1 and Box N. If the pair of analog inputs are equal, the comparator 714 does not produce any output. However, if the analog inputs are unequal, an output is produced, and when this output exceeds an absolute value difference as determined by a threshold circuit 716, an error pulse is generated. An AND gate 718 is responsive when proximity switch 130 is actuated and the error pulse is generated to gate an error signal to delay C unit 136. This causes the book of signatures to be diverted at station 48, as previously described with reference to FIG. 1.

If conditions which affect the thickness of signatures change substantially, a new trail run can be initiated in order to record in the memory 680 new thicknesses of signatures for use in controlling the production run.

We claim:

1. In a collating and binding system having a plurality of feeder means each responsive to actuation of an associated delivery means for delivering a signature to an adjacent station spaced along a conveyor, and processing means adjacent said conveyor for processing the books of signatures which have been progressively built by the feeder means to provide output books of signatures, the improvement comprising:

source means having a plurality of outputs each corresponding to a different one of the plurality of feeder means, the source means generating a series of different combinations of signals at the plurality of outputs to form different books of signatures;

a plurality of delay means each coupled between a different one of the outputs and a different one of the feeder means for selectively actuating the associated delivery means when signals are present at the associated outputs to progressively build said plurality of different books at the spaced stations;

said processing means includes adjustable means having different positions for processing different thicknesses of books of signatures built by said feeder means;

movable shaft means responsive to a total thickness signal for moving a shaft by a corresponding amount, the shaft driving said adjustable means to alternatively assume different positions corresponding to the total thickness signal; and

summer means coupled to the plurality of outputs for summing each series of different combinations of signals to generate the total thickness signal coupled to the movable shaft means.

2. The improvement of claim 1 wherein said processing means includes stitcher means for binding said books of signature, said stitcher means including stitcher head means, stitcher drive means for producing reciprocating motion of said stitcher head means to bind an adjacent book of signatures, said adjustable means includes link means between said stitcher head means and said stitcher drive means for moving said stitcher head means to different positions, the shaft of the movable shaft means being coupled to auxiliary link means for moving said first named link means to different positions.

3. The improvement of claim 2 including synchronization means for causing said total thickness signals to control said movable shaft means when said particular combination of signatures is adjacent said stitcher head means.

4. The improvement of claim 1 wherein said processing means includes mailing applicator means for attaching individual mailing labels to a book of signatures carried by a mailing carrier means, said adjustable means comprises height means for adjusting the relative height between said applicator means and said carrier means, and the shaft of the movable shaft means controls said height means to compensate for different thicknesses of the books of signatures.

5. The improvement of claim 4 wherein said mailing labels each carry coded indicia representing a desired combination of signatures, the source means includes reader means for reading said coded indicia to generate the desired combination of signals at the plurality of outputs, and synchronization means for causing the mailing label which controls selective actuation to be applied to the corresponding combination of signatures resulting therefrom when reaching the mailing carrier means.

6. The improvement of claim 1 wherein said source means includes programmable selector means for decoding a coded indicia to generate the series of different combinations of signals, said programmable selector means includes a plurality of switch means manually selectable to change the combinations of signals produced at the plurality of outputs by the same coded indicia.

7. The improvement of claim 1. including caliper means adjacent said conveyor for generating a caliper signal representing a monitored thickness of the combinations of signatures conveyed thereby, comparator means responsive to said caliper means and said summermeans for determining if the monitored thickness corresponds to the total thickness signal, and reject means for rejecting a monitored combination of signatures when the comparator means indicates a predetermined degree of dissimilarity.

8. The improvement of claim 7 including replacement means adjacent said conveyor for storing a plurality of replacement books of signatures, and control means for actuating said replacement means to convey a replacement book of signatures to a conveyor station at which a book of signatures has been rejected by said reject means.

9. In a collating and binding system having a plurality of feeder means each with control means actuable to deliver a signature to an adjacent station spaced along a conveyor, processing means adjacent said conveyor with control means actuable for processing the signatures at an adjacent station spaced along the conveyor to produce output books of signatures, and drive means for moving the stations of said conveyor, the improvement comprising:

sensing means associated with one of the feeder means or processing means for generating a reference signal when the drive means has moved a station to a predetermined position with respect to an adjacent station position at which the associated control means is to be actuated;

source means for generating an actuation signal prior to the time of occurrence of the reference signal; delay means coupled between said source means and said associated control means for delaying the actuation signal in order to actuate said associated control means when the drive means has moved a station to said adjacent position, including increment delay means for establishing a plurality of increment time periods occurring in synchronism with increments of movement produced by said drive means, and

variable delay means in series with said increment delay means for producing a plurality of different time periods which represent fractions of said increment time periods; and

adjustment means responsive to the reference signal for selecting a particular one of said time period fractions for said variable delay means.

10. The improvement of claim 9 wherein said increment delay means comprise first shift register means for shifting said actuation signal in response to each generation of a first shift pulse, shift control means for generating first shift pulses in response to incremental movements of the stations, said variable delay means comprise second shift register means for shifting said actuation signal in response to each generation of a second shift pulse, and means for generating second shift pulses at a higher frequency than the frequency of said first shift pulses.

11. The improvement of claim 10 wherein said sensing means includes timing cycle means for generating the reference signal at a predetermined time in the cycle of operation of the associated one feeder means or processing means, and said adjustment means is responsive to said reference signal for automatically adjusting the effective length of said second shift register means.

12. The improvement of claim 9 wherein each of said feeder means includes delivery means actuable for delivering a signature to an adjacent station spaced along said conveyor means, one of said delivery means corresponding to said associated control means.

13'. The improvement of claim 12 wherein the source means establishes a series of different combinations of signatures which are to be serially produced, and selective means responsive to said source means for selectively generating individual ones of said actuation signals for coupling by associated ones of the delay means to the associated delivery means when the spaced station adjacent the associated feeder means is to contain a signature stored by the associated feeder means.

14. The improvement of claim 12 including a plurality of detector means each associated with a different feeder means for detecting a malfunction which would produce an imperfect book, disable means operated in synchronism with said drive means for sequentially disabling each delivery means as a selected one of the stations of the conveyor means is sequentially moved adjacent each feeder means, and means coupled to said plurality of detector means for causing said disable means to disable the feeder means at which a malfunction is detected in order to effectively override the actuation signals from the delay means.

15. In a collating and binding system having a plurality of feeder means for delivering signatures to a plural ity of stations along conveyor means and processing means adjacent said conveyor means for processing books of signatures progressively built by the feeder means, the improvement comprising:

source means for establishing a series of different books of signatures which are to be sequentially delivered by said feeder means;

feeder control means responsive to said source means for selectively actuating said feeder means to progressively build the different books of signatures;

error means responsive to a malfunction which would produce an imperfect book for generating a malfunction signal;

diverter means responsive to the malfunction signal for diverting a single book of signatures corresponding to the imperfect book from said conveyor means to create an open station;

replacement means for storing a plurality of replacement books of signatures, including delivery means actuable to feed a single replacement book of signatures to said conveyor means; and control means for actuating said delivery means to fill the open station with the replacement book of signatures to cause the different books of signatures on said conveyor means to remain in synchronization with the series of different books established by the source means. 16. The improvement of claim 15 wherein said control means includes switch means adjacent said conveyor means for detecting the open station, and means responsive to said switch means for actuating said delivery means.

17. The improvement of claim 15 wherein said source means includes a series of mailing labels corresponding to said series of different books, and said processing means includes mailing head means for affixing individual ones of said mailing labels to the series of books and replacement books carried by the conveyor means to maintain the mailing labels in synchronism with the series of different books which correspond thereto.

18. In a collating and binding system having a plurality of feeder means for delivering signatures to a plurality of stations along conveyor means and processing means adjacent said conveyor means for processing books of signatures progressively built by the feeder means, the improvement comprising:

diverter means responsive to a predetermined condition for diverting a single book of signatures from said conveyor means to create an open station;

book hopper means for storing a plurality of replacement books of signatures, including an active storage section with delivery means actuable to feed a single replacement book of signatures to said conveyor means and a buffer storage section for storing replacement books for the active storage sec tion, detector means associated with said active storage section for determining when additional replacement books are required from said buffer storage means, and controller means responsive to said detector means for transferring a predetermined number of replacement books from said buffer storage means to said active storage means; and

control means for actuating said delivery means to fill the open station with the replacement book of signatures.

19. The improvement of claim 18 wherein said delivery means includes vacuum means for gripping an individual one of said replacement books in said active storage section, replacement conveyor means for conveying the replacement book to the open station of said conveyor means, shuttle means for moving said vacuum means between said active storage section and said replacement conveyor means, and said control means includes valve means for controlling the vacuum to said vacuum means.

20. In a collating system having a plurality of feeder means each responsive to actuation of an associated delivery means for delivering a signature to an adjacent station spaced along a collating conveyor, and drive means for operating the collating conveyor to progressively build a plurality of books of signatures at the plurality of spaced stations, the improvement comprising:

source means for establishing a series of coded indicia of different combinations to represent difierent combinations of signatures which are to be serially delivered from the collating conveyor as different books of signatures,

decoder means coupled to the source means and responsive to each coded indicia for generating at a plurality of outputs a plurality of actuation signals with each actuation signal representing a different signature which is to be delivered to the collating conveyor,

a plurality of delay means each associated with a different delivery means and having a time delay corresponding to the time necessary for a spaced station to be driven from a reference position to the associated feeder means, each delay means being responsive when one of the actuation signals is coupled thereto to selectively actuate the associated delivery means after the lapse of the corresponding time delay,

a plurality of manually actuable switches greater than the plurality of delay means with at least two manually actuable switches being associated with one of the delay means, and

circuit means for connecting said plurality of manually actuable switches between said decoder means and the plurality of delay means with said at least two switches being actuable to connect either one or another output of the decoder means to the same delay means to cause the same actuation signal to actuate differentdelivery means as controlled by the programming of the plurality of switches.

21. The improvement of claim wherein the plurality of manually actuable switches includes a switch for connecting each output of the decoder means to any one of the plurality of delay means in order to form a matrix of switches which allows any actuation signal at an output to actuate any one of the delay means.

22. The improvement of claim 20 wherein said source means includes a series of mailing labels and an associated series of coded indicia each formed of plural marks, reader means for reading the plural marks to develop a plurality of actuation signals greater than the number of plural marks, said collating system includes mailing head means for applying said series of mailing labels to said combinations of signatures in synchronism with the series of coded indicia which controlled actuation of the delivery means.

23. The improvement of claim 22 wherein said plural marks comprise different letters having substantially parallel lines representing binary bits, said letters containing a number of possible combinations of lines greater than the number of letters, the decoder means having a number of output lines greater than the number of letters and corresponding to the number of possible combinations, and a coding-to-decimal circuit responsive to the binary bits for generating on the output lines the actuation signals which correspond to the binary bits. I

24. The improvement of claim 20 wherein at least one of said plurality of delay means includes fixed delay means for shifting actuation signals stored therein in response to incremental movements of the collating conveyor and variable delay means for shifting the actuation signals in response to fractional increments of movement of said collating conveyor.

25. The improvement of claim 24 wherein the feeder means associated with the at least one delay means includes timing means for generating a timing signal when the associated delivery means should be actuated to properly deliver a signature to an adjacent station, and said variable delay means includes timing compensation means automatically responsive to different occurrences of said timing signal for automatically varying the fractional time delay produced by said variable delay means.

26. In a collating system having a plurality of feeder means each responsive to actuation of an associated delivery means for delivering a signature to an adjacent station spaced along a collating conveyor, and drive means for operating the collating to progressively build a plurality of books of signatures at the plurality of spaced stations, the improvement comprising:

source means for establishing a series of different combinations of coded indicia which represent different combinations of signatures which are to be serially delivered from the collating conveyor as different books of signatures;

first reader means for reading the coded indicia from the source means to generate a plurality of actuation signals which are to actuate different ones of the delivery means in accordance with the different combinations of signatures represented by the coded indicia;

selective means responsive to the first reader means for selectively actuating individual delivery means when the associated feeder means contains a signature which the source means indicates by the presence of the actuation signals is to be included in the combination of signatures on the spaced station adjacent the associated feeder means;

second reader means for reading the coded indicia from the source means after the coded indicia has been coupled from the first reader means to the selective means to develop a total thickness signal representing the thickness of the combination of signatures represented by the coded indicia; and

caliper means for generating an error indication when a measured thickness of signatures on the collating conveyor does not match the total thickness signal from the second reader means.

27. The improvement of claim 26 including selector means responsive to the coded indicia at an input for generating feeder signals at a plurality of outputs corresponding to the plurality of feeder means, summer means for summing the feeder signals to generate the total thickness signal, and coupling means for coupling the input of the selector means to the second reader means and the outputs of the selector means to the summer means.

28. The improvement of claim 27 wherein the coupling means comprises a multiplexer for coupling the first reader means to the input of the selector means 

1. In a collating and binding system having a plurality of feeder means each responsive to actuation of an associated delivery means for delivering a signature to an adjacent station spaced along a conveyor, and processing means adjacent said conveyor for processing the books of signatures which have been progressively built by the feeder means to provide output books of signatures, the improvement comprising: source means having a plurality of outputs each corresponding to a different one of the plurality of feeder means, the source means generating a series of different combinations of signals at the plurality of outputs to form different books of signatures; a plurality of delay means each coupled between a different one of the outputs and a different one of the feeder means for selectively actuating the associated delivery means when signals are present at the associated outputs to progressively build said plurality of different books at the spaced stations; said processing means includes adjustable means having different positions for processing different thicknesses of books of signatures built by said feeder means; movable shaft means responsive to a total thickness signal for moving a shaft by a corresponding amount, the shaft driving said adjustable means to alternatively assume different positions corresponding to the total thickness signal; and summer means coupled to the plurality of outputs for summing each series of different combinations of signals to generate the total thickness signal coupled to the movable shaft means.
 2. The improvement of claim 1 wherein said processing means includes stitcher means for binding said books of signature, said stitcher means including stitcher head means, stitcher drive means for producing reciprocating motion of said stitcher head means to bind an adjacent book of signatures, said adjustable means includes link means between said stitcher head means and said stitcher drive means for moving said stitcher head means to different positions, the shaft of the movable shaft means being coupled to auxiliary link means for moving said first named link means to different positions.
 3. The improvement of claim 2 including synchronization means for causing said total thickness signals to control said movable shaft means when said particular combination of signatures is adjacent said stitcher head means.
 4. The improvement of claim 1 wherein said processing means includes mailing applicator means for attaching individual mailing labels to a book of signatures carried by a mailing carrier means, said adjustable means comprises height means for adjusting the relative height between said applicator means and said carrier means, and the shaft of the movable shaft means controls said height means to compensate for different thicknesses of the books of signatures.
 5. The improvement of claim 4 wherein said mailing labels each carry coded indicia representing a desired combination of signatures, the source means includes reader means for reading said coded indicia to generate the desired combination of signals at the plurality of outputs, and synchronization meaNs for causing the mailing label which controls selective actuation to be applied to the corresponding combination of signatures resulting therefrom when reaching the mailing carrier means.
 6. The improvement of claim 1 wherein said source means includes programmable selector means for decoding a coded indicia to generate the series of different combinations of signals, said programmable selector means includes a plurality of switch means manually selectable to change the combinations of signals produced at the plurality of outputs by the same coded indicia.
 7. The improvement of claim 1 including caliper means adjacent said conveyor for generating a caliper signal representing a monitored thickness of the combinations of signatures conveyed thereby, comparator means responsive to said caliper means and said summer means for determining if the monitored thickness corresponds to the total thickness signal, and reject means for rejecting a monitored combination of signatures when the comparator means indicates a predetermined degree of dissimilarity.
 8. The improvement of claim 7 including replacement means adjacent said conveyor for storing a plurality of replacement books of signatures, and control means for actuating said replacement means to convey a replacement book of signatures to a conveyor station at which a book of signatures has been rejected by said reject means.
 9. In a collating and binding system having a plurality of feeder means each with control means actuable to deliver a signature to an adjacent station spaced along a conveyor, processing means adjacent said conveyor with control means actuable for processing the signatures at an adjacent station spaced along the conveyor to produce output books of signatures, and drive means for moving the stations of said conveyor, the improvement comprising: sensing means associated with one of the feeder means or processing means for generating a reference signal when the drive means has moved a station to a predetermined position with respect to an adjacent station position at which the associated control means is to be actuated; source means for generating an actuation signal prior to the time of occurrence of the reference signal; delay means coupled between said source means and said associated control means for delaying the actuation signal in order to actuate said associated control means when the drive means has moved a station to said adjacent position, including increment delay means for establishing a plurality of increment time periods occurring in synchronism with increments of movement produced by said drive means, and variable delay means in series with said increment delay means for producing a plurality of different time periods which represent fractions of said increment time periods; and adjustment means responsive to the reference signal for selecting a particular one of said time period fractions for said variable delay means.
 10. The improvement of claim 9 wherein said increment delay means comprise first shift register means for shifting said actuation signal in response to each generation of a first shift pulse, shift control means for generating first shift pulses in response to incremental movements of the stations, said variable delay means comprise second shift register means for shifting said actuation signal in response to each generation of a second shift pulse, and means for generating second shift pulses at a higher frequency than the frequency of said first shift pulses.
 11. The improvement of claim 10 wherein said sensing means includes timing cycle means for generating the reference signal at a predetermined time in the cycle of operation of the associated one feeder means or processing means, and said adjustment means is responsive to said reference signal for automatically adjusting the effective length of said second shift register means.
 12. The improvement of claim 9 wherein each of said feeder means includes delivery means actuable for delivering a signature to an adjacent station spaced along said conveyor means, one of said delivery means corresponding to said associated control means.
 13. The improvement of claim 12 wherein the source means establishes a series of different combinations of signatures which are to be serially produced, and selective means responsive to said source means for selectively generating individual ones of said actuation signals for coupling by associated ones of the delay means to the associated delivery means when the spaced station adjacent the associated feeder means is to contain a signature stored by the associated feeder means.
 14. The improvement of claim 12 including a plurality of detector means each associated with a different feeder means for detecting a malfunction which would produce an imperfect book, disable means operated in synchronism with said drive means for sequentially disabling each delivery means as a selected one of the stations of the conveyor means is sequentially moved adjacent each feeder means, and means coupled to said plurality of detector means for causing said disable means to disable the feeder means at which a malfunction is detected in order to effectively override the actuation signals from the delay means.
 15. In a collating and binding system having a plurality of feeder means for delivering signatures to a plurality of stations along conveyor means and processing means adjacent said conveyor means for processing books of signatures progressively built by the feeder means, the improvement comprising: source means for establishing a series of different books of signatures which are to be sequentially delivered by said feeder means; feeder control means responsive to said source means for selectively actuating said feeder means to progressively build the different books of signatures; error means responsive to a malfunction which would produce an imperfect book for generating a malfunction signal; diverter means responsive to the malfunction signal for diverting a single book of signatures corresponding to the imperfect book from said conveyor means to create an open station; replacement means for storing a plurality of replacement books of signatures, including delivery means actuable to feed a single replacement book of signatures to said conveyor means; and control means for actuating said delivery means to fill the open station with the replacement book of signatures to cause the different books of signatures on said conveyor means to remain in synchronization with the series of different books established by the source means.
 16. The improvement of claim 15 wherein said control means includes switch means adjacent said conveyor means for detecting the open station, and means responsive to said switch means for actuating said delivery means.
 17. The improvement of claim 15 wherein said source means includes a series of mailing labels corresponding to said series of different books, and said processing means includes mailing head means for affixing individual ones of said mailing labels to the series of books and replacement books carried by the conveyor means to maintain the mailing labels in synchronism with the series of different books which correspond thereto.
 18. In a collating and binding system having a plurality of feeder means for delivering signatures to a plurality of stations along conveyor means and processing means adjacent said conveyor means for processing books of signatures progressively built by the feeder means, the improvement comprising: diverter means responsive to a predetermined condition for diverting a single book of signatures from said conveyor means to create an open station; book hopper means for storing a plurality of replacement books of signatures, including an active storage section with delivery means actuable to feed a single replacement book of signatures to said conveyor means and a buffer storage section for storing repLacement books for the active storage section, detector means associated with said active storage section for determining when additional replacement books are required from said buffer storage means, and controller means responsive to said detector means for transferring a predetermined number of replacement books from said buffer storage means to said active storage means; and control means for actuating said delivery means to fill the open station with the replacement book of signatures.
 19. The improvement of claim 18 wherein said delivery means includes vacuum means for gripping an individual one of said replacement books in said active storage section, replacement conveyor means for conveying the replacement book to the open station of said conveyor means, shuttle means for moving said vacuum means between said active storage section and said replacement conveyor means, and said control means includes valve means for controlling the vacuum to said vacuum means.
 20. In a collating system having a plurality of feeder means each responsive to actuation of an associated delivery means for delivering a signature to an adjacent station spaced along a collating conveyor, and drive means for operating the collating conveyor to progressively build a plurality of books of signatures at the plurality of spaced stations, the improvement comprising: source means for establishing a series of coded indicia of different combinations to represent different combinations of signatures which are to be serially delivered from the collating conveyor as different books of signatures, decoder means coupled to the source means and responsive to each coded indicia for generating at a plurality of outputs a plurality of actuation signals with each actuation signal representing a different signature which is to be delivered to the collating conveyor, a plurality of delay means each associated with a different delivery means and having a time delay corresponding to the time necessary for a spaced station to be driven from a reference position to the associated feeder means, each delay means being responsive when one of the actuation signals is coupled thereto to selectively actuate the associated delivery means after the lapse of the corresponding time delay, a plurality of manually actuable switches greater than the plurality of delay means with at least two manually actuable switches being associated with one of the delay means, and circuit means for connecting said plurality of manually actuable switches between said decoder means and the plurality of delay means with said at least two switches being actuable to connect either one or another output of the decoder means to the same delay means to cause the same actuation signal to actuate different delivery means as controlled by the programming of the plurality of switches.
 21. The improvement of claim 20 wherein the plurality of manually actuable switches includes a switch for connecting each output of the decoder means to any one of the plurality of delay means in order to form a matrix of switches which allows any actuation signal at an output to actuate any one of the delay means.
 22. The improvement of claim 20 wherein said source means includes a series of mailing labels and an associated series of coded indicia each formed of plural marks, reader means for reading the plural marks to develop a plurality of actuation signals greater than the number of plural marks, said collating system includes mailing head means for applying said series of mailing labels to said combinations of signatures in synchronism with the series of coded indicia which controlled actuation of the delivery means.
 23. The improvement of claim 22 wherein said plural marks comprise different letters having substantially parallel lines representing binary bits, said letters containing a number of possible combinations of lines greater than the number of letters, the decoder means having a number of output lines greater than The number of letters and corresponding to the number of possible combinations, and a coding-to-decimal circuit responsive to the binary bits for generating on the output lines the actuation signals which correspond to the binary bits.
 24. The improvement of claim 20 wherein at least one of said plurality of delay means includes fixed delay means for shifting actuation signals stored therein in response to incremental movements of the collating conveyor and variable delay means for shifting the actuation signals in response to fractional increments of movement of said collating conveyor.
 25. The improvement of claim 24 wherein the feeder means associated with the at least one delay means includes timing means for generating a timing signal when the associated delivery means should be actuated to properly deliver a signature to an adjacent station, and said variable delay means includes timing compensation means automatically responsive to different occurrences of said timing signal for automatically varying the fractional time delay produced by said variable delay means.
 26. In a collating system having a plurality of feeder means each responsive to actuation of an associated delivery means for delivering a signature to an adjacent station spaced along a collating conveyor, and drive means for operating the collating to progressively build a plurality of books of signatures at the plurality of spaced stations, the improvement comprising: source means for establishing a series of different combinations of coded indicia which represent different combinations of signatures which are to be serially delivered from the collating conveyor as different books of signatures; first reader means for reading the coded indicia from the source means to generate a plurality of actuation signals which are to actuate different ones of the delivery means in accordance with the different combinations of signatures represented by the coded indicia; selective means responsive to the first reader means for selectively actuating individual delivery means when the associated feeder means contains a signature which the source means indicates by the presence of the actuation signals is to be included in the combination of signatures on the spaced station adjacent the associated feeder means; second reader means for reading the coded indicia from the source means after the coded indicia has been coupled from the first reader means to the selective means to develop a total thickness signal representing the thickness of the combination of signatures represented by the coded indicia; and caliper means for generating an error indication when a measured thickness of signatures on the collating conveyor does not match the total thickness signal from the second reader means.
 27. The improvement of claim 26 including selector means responsive to the coded indicia at an input for generating feeder signals at a plurality of outputs corresponding to the plurality of feeder means, summer means for summing the feeder signals to generate the total thickness signal, and coupling means for coupling the input of the selector means to the second reader means and the outputs of the selector means to the summer means.
 28. The improvement of claim 27 wherein the coupling means comprises a multiplexer for coupling the first reader means to the input of the selector means and the plurality of outputs to the plurality of delivery means, and for alternatively coupling the second reader means to the input of the selector means and the plurality of outputs to the summer means, whereby the selector means is used in common by the first reader means and the second reader means.
 29. The improvement of claim 26 in which the collating system includes processing means adjacent the collating conveyor processing the books of signatures which have been progressively built at the plurality of spaced stations, the processing means includes adjustable means having different positions for procEssing different thicknesses of books of signatures and movable shaft means for moving a shaft by an amount corresponding to the total thickness signal from the second reader means, the shaft driving the adjustable means to different positions corresponding to the total thickness signal. 